Erosion Control November/December 2016 : Page 20

replaced and reforested.” Blankets and new plantings The replacements around a stormwater basin for the trees that were removed were “thousands of seedlings of native trees—upwards of 20,000 plants along the roadway to help with stormwater runoff.” The seedlings included various species of oak and maple trees. When these seedlings grow into mature trees, drivers on this busy road will see a restored forest. Reflecting on how erosion control work has evolved, Kreutzer says, “what an important part of the construction process erosion control has become. All Straw to cover the soil would have that paving and concrete means you been cost effective, but “they didn’t don’t have grass growing. The work want us to use straw because it would comes down to landscaping and grass. be blown over the neighborhood,” They have to be growing and healthy says Marsh. before the project can be closed out.” Something was needed to prevent dust or soil leaving the site because of A High-Proﬁ le Job in Oregon rain or wind, to keep adjoining private Fox Erosion Control and Landscap-properties clean, and assuage environ-ing in Clackamas, OR, uses Profile mental concerns. Whatever was used Products’ Flexterra on many jobs. had to cover the soil and also have an The product was an essential part of a acceptable appearance. particular highway project that Fox did, “Every Friday before the project shut along with general contractor Wildish down for the weekend, any open soil we Standard Paving of Eugene, OR. saw, we would cover it with Flexterra,” “This was the first project where says Marsh. we had an opportunity to introduce The total area covered with Flexterra Flexterra High-Performance Flexible was about four acres. The product’s Growth Medium to ODOT [Oregon overall green appearance was acceptable, Department of Transportation],” says and provided a visual assurance that the Terry Marsh, president of Fox. contractor was protecting the environ-The work involved a change order ment and the residents’ homes. project on the south west Iowa Street Marsh says that Flexterra worked Viaduct Bridge over Interstate 5 in perfectly. “That one project opened downtown Portland, OR. The location the door to ODOT taking a serious was close to an affluent neighborhood. look at the product at the state and the “There were lots of slopes; steep county level. That one project changed terraces had been opened up. Lots of a lot of people’s minds about Flexterra people were complaining and lots of as a replacement for erosion control people were watching the project. Their straw mats.” homes are nice, and they were very The crews shot the Flexterra from concerned about runoff, dust, and silt a Finn T330 HydroSeeder. Marsh says getting into nearby streams and fish that people often ask if Flexterra mixes hatcheries,” explains Marsh. well in a hydroseeding machine and The residents were concerned about if it can be applied when the weather dirt—which the Oregon rains would is rainy or misty. “Because it’s a long quickly turn into mud. The site was an wood fiber, rather than a shorter fiber, eyesore and, given the steep terrain, a and because it has an aggressive tacki-potential environmental problem. fier, it mixes up into a pretty viscous 20 EROSION CONTROL RAM-T CORP. mixture. You can’t mix up as much as you can with regular fiber mulch, so you’ll be doing more applications to get out the same amount,” he notes. As for using Flexterra during wet weather, “we can shoot when it’s raining, as long as it’s not pouring. With a drizzle it sets itself up well.” Noting the differ-ences in tackifiers, Marsh says, “Flexterra seeps down into the soil and helps the product to secure itself to the soil, rather than to secure it to itself.” He feels that the project showed that Flexterra, even though more expensive than straw, “could be done expedi-tiously, whereas using straw was labor intensive, with higher labor costs.” The I-5 project started in July 2010, and lasted until October 2014. Some sections were covered with Flexterra multiple times to stabilize soil that had been disturbed since the previous week’s covering. By the completion date, Fox had shot enough Flexterra to cover 26 acres. Marsh says that rain is usually a factor on projects. “Oregon gets its fair share year around. In the coastal mountains, it’s 80 inches of rain annu-ally. In the Willamette Valley where Portland is, it’s 40 to 50 inches a year.” Besides wet weather, “traffic was a significant issue. We always had to con-tend with heavy traffic. I-5 is the largest freeway, and the most traveled in the state of Oregon,” he adds. Heavy traffic affects access, so work-ers and materials can take longer to travel to and from the site. “There were long loops we had to make if we were shooting more than one area.” The Fox crews had to wait on Fri-days for all of the other work on the site to be finished, and that put them squarely into general rush-hour traffic. “We didn’t finish on Fridays until seven or eight at night,” recalls Marsh. For the final hydroseeding on the project, Fox used mycorrhizae at 10 pounds per acre, Flexterra at 3,000 WWW.EROSIONCONTROL.COM